diff --git a/pygeoapi/api.py b/pygeoapi/api.py
index 7645e04..2d1bb53 100644
--- a/pygeoapi/api.py
+++ b/pygeoapi/api.py
@@ -1196,9 +1196,9 @@ class API:
                 LOGGER.debug('Adding EDR links')
                 parameters = p.get_fields()
                 if parameters:
-                    collection['parameter-names'] = {}
+                    collection['parameter_names'] = {}
                     for f in parameters['field']:
-                        collection['parameter-names'][f['id']] = f
+                        collection['parameter_names'][f['id']] = f
 
                 for qt in p.get_query_types():
                     collection['links'].append({
@@ -3764,8 +3764,8 @@ class API:
                 HTTPStatus.BAD_REQUEST, headers, request.format,
                 'InvalidParameterValue', msg)
 
-        LOGGER.debug('Processing parameter-name parameter')
-        parameternames = request.params.get('parameter-name') or []
+        LOGGER.debug('Processing parameter_names parameter')
+        parameternames = request.params.get('parameter_names') or []
         if isinstance(parameternames, str):
             parameternames = parameternames.split(',')
 
@@ -3841,7 +3841,7 @@ class API:
 
         if parameternames and not any((fld['id'] in parameternames)
                                       for fld in p.get_fields()['field']):
-            msg = 'Invalid parameter-name'
+            msg = 'Invalid parameter_names'
             return self.get_exception(
                 HTTPStatus.BAD_REQUEST, headers, request.format,
                 'InvalidParameterValue', msg)
diff --git a/tests/test_api.py b/tests/test_api.py
index 4e522c3..582bb6e 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -1883,7 +1883,7 @@ def test_get_collection_edr_query(config, api_):
     req = mock_request()
     rsp_headers, code, response = api_.describe_collections(req, 'icoads-sst')
     collection = json.loads(response)
-    parameter_names = list(collection['parameter-names'].keys())
+    parameter_names = list(collection['parameter_names'].keys())
     parameter_names.sort()
     assert len(parameter_names) == 4
     assert parameter_names == ['AIRT', 'SST', 'UWND', 'VWND']
@@ -1905,9 +1905,9 @@ def test_get_collection_edr_query(config, api_):
         req, 'icoads-sst', None, 'position')
     assert code == HTTPStatus.BAD_REQUEST
 
-    # bad parameter-name parameter
+    # bad parameter_names parameter
     req = mock_request({
-        'coords': 'POINT(11 11)', 'parameter-name': 'bad'
+        'coords': 'POINT(11 11)', 'parameter_names': 'bad'
     })
     rsp_headers, code, response = api_.get_collection_edr_query(
         req, 'icoads-sst', None, 'position')
@@ -1938,7 +1938,7 @@ def test_get_collection_edr_query(config, api_):
 
     # single parameter
     req = mock_request({
-        'coords': 'POINT(11 11)', 'parameter-name': 'SST'
+        'coords': 'POINT(11 11)', 'parameter_names': 'SST'
     })
     rsp_headers, code, response = api_.get_collection_edr_query(
         req, 'icoads-sst', None, 'position')
@@ -2055,7 +2055,7 @@ def test_get_collection_edr_query(config, api_):
     # cube decreasing latitude coords and S3
     req = mock_request({
         'bbox': '-100,40,-99,45',
-        'parameter-name': 'tmn',
+        'parameter_names': 'tmn',
         'datetime': '1994-01-01/1994-12-31',
     })